Various meter assemblies of the type frequently referred to as compound meters have heretofore been provided for measuring variable flow rates within a piping system. Such assemblies, however, because of certain structural characteristics have been beset with one or more of the following shortcomings: the assembly is incapable of accurately measuring the flow rate where the latter varies over a wide range; the assembly is of bulky, costly and complex construction; the flow paths through the assembly are such that substantial pressure drops occur within the assembly; the assembly is susceptible to harmonic oscillation or chattering when measuring the liquid flow; and servicing of the assembly is a difficult and awkward operation requiring shut down of the assembly for long periods of time and oftentimes requiring removal of the entire assembly from the piping system.